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Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission uid (don’t over ll),
engine oil, axle lubricant, belts, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you nd them quickly. If
you’re trailering, it’s a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
Heavy-Duty Trailer Wiring Package
Your vehicle is equipped with the seven-wire trailer
towing harness. This harness with a seven-pin universal
heavy-duty trailer connector is attached to a bracket
on the hitch platform.
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Service............................................................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Speci cations....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-7
Fuels in Foreign Countries...............................5-8
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Oil Life System..................................5-16
Engine Air Cleaner/Filter................................5-18
Automatic Transmission Fluid.........................5-21
Engine Coolant.............................................5-23
Coolant Surge Tank Pressure Cap..................5-26
Engine Overheating.......................................5-26
Overheated Engine Protection
Operating Mode........................................5-28
Cooling System............................................5-28
Engine Fan Noise.........................................5-33Power Steering Fluid.....................................5-33
Windshield Washer Fluid................................5-34
Brakes........................................................5-36
Battery........................................................5-39
Jump Starting...............................................5-40
All-Wheel Drive..............................................5-45
Rear Axle.......................................................5-45
Front Axle......................................................5-46
Headlamp Aiming...........................................5-48
Headlamp Horizontal Aiming...........................5-49
Headlamp Vertical Aiming..............................5-50
Bulb Replacement..........................................5-51
High Intensity Discharge (HID) Lighting............5-51
Halogen Bulbs..............................................5-52
Headlamps..................................................5-52
Front Turn Signal, Sidemarker and Daytime
Running Lamps.........................................5-56
Taillamps, Turn Signal, Sidemarker, Stoplamps
and Back-up Lamps...................................5-57
Replacement Bulbs.......................................5-58
Windshield Wiper Blade Replacement..............5-58
Tires..............................................................5-59
Tire Sidewall Labelling...................................5-60
Tire Terminology and De nitions.....................5-63
In ation - Tire Pressure.................................5-65
Section 5 Service and Appearance Care
5-1
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Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you will go to your dealer
for all your service needs. You will get genuine GM parts
and GM-trained and supported service people.
We hope you will want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
California Proposition 65 Warning
Most motor vehicles, including this one, contain and/or
emit chemicals known to the State of California to
cause cancer and birth defects or other reproductive
harm. Engine exhaust, many parts and systems
(including some inside the vehicle), many uids, and
some component wear by-products contain and/or emit
these chemicals.
5-3
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